Case Study: Distributed Wi-Fi Control

With IEEE 802.11n significantly ratcheting up the amount of traffic that can be generated from a wireless network, large Wi-Fi deployments — such as the one at National Autonomous University of Mexico — may greatly benefit from a wireless solution that delivers distributed intelligence and maximum redundancy at the edge, rather than packing it into centralised controllers housed in the data centre.

Aerohive Networks has been at the forefront of the distributed architecture movement for several years, as its cooperative control protocols spread controller functions among all access points, rather than centralising them on an expensive piece of data centre hardware. With access points that self-organise into hives to share control plane information, the distributed architecture still provides advanced functions such as fast layer 2 and layer 3 roaming, cooperative RF management, security and mesh networking.

Minimising traffic flow

Other wireless LAN vendors have paid heed to the distributed movement over the last few years, splitting the management, control and data planes to minimise the amount of traffic that needs to flow back to the controller while putting back some intelligence to the access point. And Meraki went so far as to take the controller out of the data centre, moving those functions to the cloud.

But now it appears that the father of controller-based architecture is even moving away from classic controller-based architecture. Motorola, which bought Symbol Technologies in 2006, also apparently will move much network intelligence closer to the edge. Symbol, of course, shipped the first controller-based architecture back in 2002.

Paraphrasing Alán Lopez, Motorola’s senior marketing manager of its WLAN Portfolio, from a YouTube video, “With 11n and the much higher throughput at the access points, it takes a little bit of rethink on the architecture side … with all that throughput, the wireless controller starts to become a bottleneck. It was really about trying to architect a paradigm that takes that bottleneck out of the equation … distributing intelligence to the access points.”

For instance, the UNAM (National Autonomous University of Mexico) faculty of Law wanted to make Wi-Fi coverage ubiquitous for mobile phones, laptops and other client devices of its almost-17,000 academics and students, a network that would cover 30,000 square meters of classrooms, auditoriums and other public spaces.  Coined “The Digital Facility,” the Wi-Fi network is intended to host telephony and video-conferencing traffic, in addition to typical Internet access, once completed.

UNAM Case Study

Along with a four-person IT team, Ruperto Patiño, UNAM faculty of Law director, wanted to make sure their solution could handle their traffic mix and volume while remaining easy to manage given limited support resources, no matter what WLAN architecture they chose. They also needed to ensure the manufacturer could provide quality support within Mexico.

“We decided on Aerohive Networks,” said Patiño. “The Aerohive network would provide the power we needed, and it would be easy to administer with our tight IT resources.”

Aerohive offers a two-tier distribution model in Mexico. A VAD (value-added dealer) called TekMart provides the first tier, with a reseller called DataTeam as the second tier. When it comes to product support, these two companies reverse roles (as both organisations employ certified Aerohive engineers), with Aerohive as the third tier.

Given Patiño’s concern about product support in Mexico, Aerohive’s controller-less architecture should be especially attractive. Not because of the technical wizardry of the architecture, but because the architecture eliminates the need for a large, expensive and possibly hard-to-replace-on-short-notice piece of hardware that could be a single point of failure for the entire network.

“Given the scope of their network deployments, universities such as UNAM require a controller-less AP architecture like Aerohive’s,” said Stephen Philip, Aerohive vice president of Product Marketing. “Controller-less APs are easy to install, easy to use, and easy to manage — offering the type of low-overhead that is needed in a sprawled out, traffic-intensive environment such as a university campus that serves hundreds to thousands of concurrent users.”